Field of the Invention
The invention relates to a data allocating method, and particularly relates to a data allocating apparatus for real-valued fast Fourier transform (RFFT) output data, a signal processing apparatus and a data allocating method.
Description of Related Art
Fast Fourier transform (FFT) has been widely applied in various real-valued signal processing techniques, for example, biomedical signal processing for cochlear implant (CI), hearing aid, epilepsy inhibition, etc. In the aforementioned applications, since the signals are required to be real numbers, a complex fast Fourier transform (CFFT) operation method is used to implement the RFFT. In order to improve operation efficiency and decrease a hardware cost, other specific algorithms such as a pipeline architecture, etc., are further provided to ameliorate the CFFT operation method.
Since calculation of amplitude of the FFT output is generally performed after real part data and corresponding imaginary part data are all generated, when only the real part data or the imaginary part data is generated, such part data is first stored to wait generation of the corresponding imaginary part data or the real part data. In the conventional signal processing apparatus, the number of storage units (for example, registers, buffers, etc.) used for storing the real part data or the imaginary part data is generally designed to be the same with FFT operation points. However, the aforementioned architecture may have a high hardware cost and low operation efficiency.